T he Main Challenge
Today’s task is to multiply two numbers together, then either add or subtract the third number to achieve the target answer of 37.
Using the formula (a×b)±c, where a, b and c are three unique digits from 1-9, one way of achieving 37 is (7×5)+2; can you find the other SEVEN ways?
[Note: (7×5)+2 = 37 and (5×7)+2 = 37 counts as just ONE way.]
The 7puzzle Challenge
The playing board of the 7puzzle game is a 7-by-7 grid containing 49 different numbers, ranging from 2 up to 84.
The 5th & 6th rows of the playing board contain the following fourteen numbers:
5 6 7 12 16 18 20 21 33 49 50 56 81 84
From the list, which three different numbers have a sum of 100?
The Lagrange Challenge
Lagrange’s Four-Square Theorem states that every positive integer can be made by adding up to four square numbers.
For example, 7 can be made by 2²+1²+1²+1² (or 4+1+1+1).
There is only ONE way to make 224 when using Lagrange’s Theorem. Can you find it?
The Mathematically Possible Challenge
Using 4, 6 and 9 once each, with + – × ÷ available, which is the ONLY number it is possible to make from the list below?
13 26 39 52 65 78 91 104 117 130
#13TimesTable
The Target Challenge
Can you arrive at 224 by inserting 1, 2, 7 and 7 into the gaps on each line?
- ◯×◯²×(◯+◯) = 224
- ◯⁵×◯³×◯²÷◯ = 224
Answers can be found here.
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